About the mapper start: client path in the Mapper.cfg must point to a properly configured 2238 client (the mapper will attempt to open the client's fonline.cfg and take dat paths from there). There shouldn't be any problems as long you do this right, but you might try running the mapper as administrator in case of any.
About testing the maps in game: the fastest and simplest way is by replacing an existing map in the SDK server with your own. Just replace, say, redding.map with yourmap.map, wipe the server (by deleting all save files in save/), start it, connect to it, and enter Redding.
If you don't want to wipe for some reasons, you can skip that part, do the rest, and type ~regenmap after entering Redding.
